Page 7 - November-2022

TECHNICAL PAPER

(a) Compressive strengths (b) Flexural strengths
Figure 2: Strength performances for mortars under long term water curing

3.2 Chemically bound water higher than that of MK blended pastes having an increasing
rate of around 10 % at 365 days relative to the CBW at 90 days.
Figure 3 (a), and (b) present the chemically bound water (CBW) Therefore, it is indicated that the incorporation of MK can
of UHPC pastes and increasing rate of CBW relative to that at obviously decrease the re-hydration degree for UHPC pastes
90 days, respectively under long term water curing from 90 to with long term water curing. It should be attributed to early
365 days. The hydration rate of pastes are significant from 90 age MK reaction in paste, which significantly refines the pore
to 210 days while that obviously decrease after 210 days. The structures of paste and brings huge difficult for generation and
[30]
rehydration degree and rate of pastes blended with MK are precipitation of hydration products at late age [31] . In addition,
markedly less than that of the references similar to the variation the permeating rate of free water into matrix blended with MK
tendency of strength. While LS has insignificant effect on should be evidently lower than that of the references, which also
inhibiting late age rehydration reaction of pastes. For instance, impedes the rehydration reaction.
the increasing rate of CBW in binary paste blended with LS
(PLS00) and cement paste (P00) are approximate (about 20 %) Additionally, its rehydration extent of PLS00 is similar to that of
at 365 days compared to the CBW at 90 days. It is obviously P00 from 90 to 150 days though LS replaced 30 % cement by

(a) CBW of pastes (b) Increasing rate of CBW
Figure 3: Chemically bound water of pastes with long term water curing

THE INDIAN CONCRETE JOURNAL | NOVEMBER 2022 21